Sorting device, in particular for pieces of luggage

ABSTRACT

A sorting device for sorting products, for example pieces of luggage, including a removing mechanism moving the product to be sorted off the supporting surface at a desired sorting location, wherein the removing mechanism includes a pusher element and a moving mechanism moving the pusher element laterally at a sorting location so as to have the pusher element push the product to be sorted off the supporting surface. The removing mechanism further includes two guides each sorting unit for guiding two respective guide members of the pusher element during the lateral movement of the pusher element.

FIELD

The present invention relates to a sorting device for sorting products,in particular pieces of luggage, comprising a number of sorting units,conveying means for moving the sorting units in a conveying directionalong a conveying path, said sorting units each comprising a carrierprovided with a supporting surface for supporting a product to besorted, said sorting device further comprising removing means for movingthe product to be sorted off the supporting surface at a desired sortinglocation, wherein the removing means comprise a pusher elementassociated with a sorting unit disposed above an associated supportingsurface, as well as moving means for moving the pusher element laterallyat a sorting location so as to have the pusher element push the productto be sorted off the supporting surface, wherein the removing meanscomprise two guides for each sorting unit for guiding two respectiveguide members of the pusher element during said lateral movement of thepusher element, wherein the moving means comprise at least onestationary guide disposed under the supporting surface at a sortinglocation, which guide extends at an angle to the conveying direction, aswell as at least one guide element connected to a pusher element foreach sorting unit for guiding cooperation of said at least one guideelement with said at least one stationary guide during transport of thesorting unit. The invention is in particular directed at sorting piecesof luggage, without categorically excluding the use of the invention forother types of products, such as packages. It is a specific feature ofpieces of luggage that they run a greater risk of catching on somethingbecause of the projecting parts such as straps and handles that piecesof luggage usually have. In addition to that, pieces of luggagetypically have a weight between 10 kg and 30 kg.

BACKGROUND

From European patent application EP 1 411 008 A1 a so-called tilt-traysorting device is known, in which an endless train of sorting units isused. Each sorting unit has a chassis and a carrier deck, which iscapable of lateral tilting movement relative to the chassis. Eachsorting unit is provided with an electric motor for tilting the carrierdeck. Tilting the carrier deck makes it possible to cause a productsupported by the load-bearing deck to slide off the load-bearing deck ata sorting location. A risk that plays a role in this regard is that apiece of luggage will catch on something or stick to the load-bearingdeck while being handled, for example because a strap catches on acorner of the carrier deck or because a piece of luggage is wet orwrapped in shrink foil, as a result of which the piece of luggage willremain present on the carrier deck or slides off the tilting deck atleast in an uncontrolled direction rather than in lateral direction inspite of the tilting of the carrier deck, as a result of which thecorrect functioning of an upstream sorting unit, of a downstream sortingunit or of the sorting unit in question itself, and thus of the entiresorting device will be at risk. Another drawback of the known sortingdevice is the fact that it is relatively costly, in particular forapplications where a limited number of pieces of luggage are to behandled, for example 3000 pieces of luggage per hour, which is a usualcapacity at medium-sized airports.

A sorting device as referred to in the introduction is known from U.S.Pat. No. 4,732,260. Said document discloses a sorting device comprisinga plurality of elongated plates positioned one behind the other, whichare oriented transversely to a conveying direction, which plates followan endless conveying path in the vertical plane. The upper sides of theupper halves of the plates each form a supporting surface for a productto be sorted. A pusher element is provided for each plate, which pusherelement is capable of reciprocating motion transversely to the conveyingdirection between two opposite ends of the respective plate for thuspushing a product off the plate at a sorting location. The pusherelement is to that end connected, via a slot in the associated plate, toa block-shaped driving element present on the opposite side of theplate. Said driving element is provided with two bores, through whichtwo guides extending transversely to the conveying direction and beingrigidly connected to the plate in question are movable. A guide elementprovided with three rollers arranged one behind the other, which rollersare to cooperate with the aforesaid stationary guide, is mounted underthe driving element via a vertical pivot pin. An important drawback ofthis known sorting device is that it is not suitable for sorting piecesof luggage. From a practical viewpoint this is caused by the fact thatthe slot that is present in each plate for the necessary connectionbetween the pusher element on the outer side of the plate and thedriving element on the inner side of the plate constitutes the risk thatprojecting parts, such as straps and handles of pieces of luggage willget stuck therein. From an economic viewpoint there is furthermore thefact that the device is too expensive for being used in an economicallysound manner with pieces of luggage, in which connection it should berealised that in view of the dimensions of each plate, seen in theconveying direction, a relatively large number of plates provided withthe associated parts as described above are needed. In addition to that,the pusher elements associated with a number of successive plates movefrom one side of the sorting device to the opposite side transversely tothe conveying direction upon sorting out a piece of luggage, to whichend the guide elements associated with the pusher elements in questionmove along the same stationary guides. During this movement, the pusherelements jointly form a pushing plane oriented at an angle to theconveying direction, causing the orientation of the pieces of luggage onthe associated plates to change. This is not always desirable. Anotherimportant drawback is the risk that the pusher element tends to take upan oblique position as soon as a force is exerted thereon at anoff-centre location along the length of the pusher element. This willadversely affect the guiding cooperation between the transverse guidesand the two bores in the driving element and result in increasedmechanical resistance and thus extra wear on various related parts. Thisadverse effect becomes stronger as the length of the pusher elementincreases.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a sorting device whichis capable of sorting products, such as in particular pieces of luggage,with a high degree of reliability and whose cost price, in particular ifsorting capacities of about 1500 to 3000 products per hour are to berealised, is comparatively low. In order to accomplish that object, thesorting device according to the present invention is in the first placecharacterised in that said moving means comprise two guide elements foreach sorting unit, which guides are connected to the respective twoguide members associated with the pusher element and which are eacharranged for guiding cooperation with said at least one stationaryguide. Using two guide elements for each sorting unit, which guideelements are each connected to one of the two guide members associatedwith the pusher element in question, achieves that the forces acting onthe pusher element when a product to be sorted is being pushed off thesupporting surface by the pusher element can be taken up as well aspossible, even if the dimensions of the pusher elements, seen in theconveying direction, are comparatively large, for example about 100 cm.The invention moreover makes it possible to sort comparatively largeproducts, such as pieces of luggage, by means of a sorting device asreferred to in the introduction, without the product in question takingup a different orientation on the supporting surface during saidsorting.

Preferably, the two guide elements are pivotally connected to theassociated guide members about respective vertical pivot axes. As aresult, the cooperation between the guide elements on the one hand andthe stationary guide on the other hand can take place along a relativelylong part of the stationary guide without any problem, thus making itpossible to bridge interruptions in the stationary guide.

A very stable operation is obtained if the two guide members areprovided on two opposite ends of the associated pusher element.

The same advantage is obtained if the two guide elements are provideddirectly below the respective associated guide members and/or if the twoguide elements are provided directly below the guides associated withthe associated guide members.

In another preferred embodiment of the device according to theinvention, at least one guide member is pivotally connected to anotherpart of the pusher element about a further pivot axis extendingperpendicularly to the associated supporting surface, or, morepreferably, the two guide members are pivotally connected to anotherpart of the pusher element about two respective further pivot axesextending perpendicularly to the associated supporting surface. Thisleads to an increased flexibility as regards the angular position thatthe pusher element assumes, or at least is capable of assuming, duringthe lateral movement of the pusher element. This in turn leads to theadditional advantage that the orientation in which a product is pushedoff the supporting surface by the pusher element can be optimally gearedto the characteristics of the sorting location in question, morespecifically the manner and/or the direction in which the products aredischarged at that location for further transport.

The characterising features of the present preferred embodiments arealso advantageous when applied in sorting devices according to the priorart. Within this framework the present invention also provides a sortingdevice for sorting products, in particular pieces of luggage, comprisinga plurality of sorting units, conveying means for moving the sortingunits in a conveying direction along a conveying path, said sortingunits each comprising a carrier having a supporting surface forindependently supporting products to be sorted, said sorting devicefurther comprising removing means for moving the product to be sortedoff the supporting surface at a desired sorting location, wherein theremoving means comprise a pusher element associated with a sorting unitdisposed above an associated supporting surface, as well as moving meansfor moving the pusher element laterally at a sorting location so as tohave the pusher element independently push the product to be sorted offthe supporting surface, wherein the removing means comprise at least oneguide for each sorting unit for guiding a guide member of the pusherelement during said lateral movement of the pusher element, and whereinat least one guide member is pivotally connected to another part of thepusher element about a pivot axis extending perpendicularly to theassociated supporting surface.

When two guide members are used, as described above, the removing meansfurthermore preferably comprise two guides for each sorting unit forguiding two respective guide members of the pusher element during saidlateral movement of the pusher element, wherein the two guide membersare pivotally connected to another part of the pusher element about tworespective further pivot axes extending perpendicularly to theassociated supporting surface.

The aforesaid flexibility is further enhanced if at least one guidemember is slidably connected, in a direction parallel to the supportingsurface, to another part of the pusher element, or alternatively, oreven in combination therewith, the length of the pusher element isvariable, in which case the pusher element is preferably of thetelescopic type. In this way it is possible to change the spacingbetween two guide members during the lateral movement of the pusherelement.

To enable the pusher element, whose longitudinal direction extendsparallel to the conveying direction, to move laterally in a very stablemanner it is in particular preferable if the moving means comprise twosuccessive stationary guides disposed under the supporting surface at asorting location, which guides extend at an angle to the conveyingdirection, with which two guides the two respective guide elements cancooperate simultaneously during transport of the sorting unit, to whichend the two stationary guides preferably extend parallel to each other.

If two guides are used, said guides are preferably provided on twoopposite sides, seen in the conveying direction, of the associatedsupporting surface. Thus the bending moments acting on the pusherelement can be reduced as much as possible, so that said pusher elementcan be designed to be as light as possible.

In a preferred embodiment which is constructionally advantageous becauseof its relative simplicity and low cost price, the two guide elementsare preferably directly connected to the two respective guide members.

Again with a view to obtaining a lower cost price, it is preferable ifthe conveying means comprise a driven chain, to which each of thesorting units is connected.

The conveying means preferably comprise friction-type drive means, whichfrictionally engage flanks of the chain for driving the chain.

In order to have the sorting units follow the conveying path asdetermined by the course of the chain as accurately as possible also inbends, it is preferable if the sorting units are pivotally connected tothe chain about still further pivot axes extending perpendicularly tothe supporting surface at two connecting positions located one behindthe other, seen in the conveying direction, whilst the sorting units areslidably connected to the chain at the location of at least one of thetwo connecting positions.

The chain advantageously extends centrally below the sorting units, seenin a direction transversely to the conveying direction, so that on theone hand the sorting units of the sorting device can readily passthrough bends both to the left and to the right, whilst on the otherhand the load on the chain can in principle be symmetrical, which isadvantageous in connection with the bending moments acting on the chain.

In particular for use in sorting pieces of luggage it is highlypreferable if the supporting surface is a closed surface. In the case ofa closed surface, with no holes of slots in the supporting surface,there is a reduced risk of projecting parts of pieces of luggage,including labels attached to pieces of luggage, catching on somethingwhen the piece of luggage in question is being pushed off the supportingsurface by the pusher element.

Another very advantageous preferred embodiment of the invention ischaracterised in that a supply conveyor is provided for supplyingproducts to be sorted to a sorting unit, with a downstream end of saidsupply conveyor terminating at a higher level than the upper side ofpusher elements passing the downstream end of the supply conveyor. Thismakes it possible to load the supporting surface with a product to besorted by passing it over a pusher element, as a result of which theproduct to be sorted can eventually be sorted out on the opposite sideof the conveying path, so that the device is no longer limited tosorting out the product to be sorted only on the side of the conveyingpath where the supply conveyor is disposed.

To prevent the product to be sorted from coming into contact with apusher element already while a sorting unit is being loaded, which mightlead to an undesirably high load on the pusher element, it isfurthermore preferable if the downstream end of the supply conveyor atleast partially extends directly above a part of the passing pusherelements.

According to another aspect of the invention, which might also beapplied in sorting devices not comprising a pusher element provided withthe associated features as described above, a preferred embodiment ofthe invention is characterised in that the sorting units are eachprovided with a closing element both at a front end and at a rear end ofthe carrier for closing the gap between the carrier and an adjacentcarrier, wherein closing elements of successive sorting units partiallyoverlap and have an at least substantially convex edge at their facingsides, at least on one longitudinal side of the sorting units. Theclosing elements between the carriers of successive sorting units reducethe risk of objects to be sorted or other objects getting between thesorting units, possibly resulting in a malfunction at that location, orof the object in question being damaged. The convex shape of the edges(on one or both longitudinal sides of the sorting units) enables thesorting units to pass also through curvilinear parts of a conveyingpath, seen in top plan view, without parts of successive sorting unitscolliding with each other.

A further improvement as regards the risk of objects getting between thecarriers of successive sorting units is realised if the convex edges ofclosing elements of successive sorting units define at leastsubstantially triangular areas within the width of the sorting units ina rectilinear part of the conveying path on at least one of thelongitudinal sides of the sorting units, which areas are at leastpartially closed by a further closing element, which is movablyconnected to one of said closing elements. The movable connectionbetween a further closing element and a closing element can be usedadvantageously when moving through a curvilinear part of the conveyingpath, during which movement the form of the triangular areas graduallychanges. Said changing form can be followed, as it were, by the movablefurther closing element.

From a constructional viewpoint it is preferable in that regard if saidfurther closing element is pivotally connected to one of the closingelements about a vertical closing pivot axis, wherein said furtherclosing element is furthermore preferably segmental in shape and saidvertical closing pivot axis extends near the point of the segmentalform.

Said further closing element preferably abuts against a stop memberunder spring pressure, as a result of which said further closing elementtends to return to the position in question.

The advantages of the present invention manifest themselves inparticular if the sorting units are pivotally interconnected about avertical pivot axis.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in more detail by means of adescription of preferred embodiments of a sorting device according tothe invention, in which reference is made to the following figures.

FIG. 1 shows a sorting device according to a preferred embodiment of thepresent invention;

FIG. 2 shows a (part of a) sorting unit forming part of the sortingdevice according to FIG. 1 in the environment in which it is used;

FIG. 3 shows an alternative embodiment for the sorting unit shown inFIG. 2, which forms part of an alternative embodiment of a sortingdevice shown in FIG. 1;

FIG. 4 a shows two sorting units according to FIG. 2 in the environmentin which they are used;

FIG. 4 b shows a detail of FIG. 4 a;

FIGS. 5 a and 5 b show two different uses of a sorting device accordingto the invention; and

FIG. 6 is a perspective top plan view of four successive sorting units.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a sorting device 1 according to a preferred embodiment ofthe invention. The sorting device 1 comprises an endless train ofsorting units 2, which will be explained in more detail yet inparticular with reference to FIGS. 2 and 3. The sorting units 2 followan endless conveying path in the conveying direction 3, which pathcomprises a number of bends in the horizontal plane and which might inprinciple also comprise bends in the vertical plane, as will beexplained in more detail yet with reference to FIG. 3, so that theconveying path could extend at different vertical levels.

On the outer side of the conveying path two supply conveyors 19 connectto the train of sorting units 2, by means of which supply conveyorsproducts 10 to be sorted can be supplied to a sorting unit 2 in asynchronized manner for loading the same. Within the framework of thepresent invention, said supplying of a product 10 to be sorted to asorting unit 2 may also take place manually or from above, in which casea supply conveyor extends directly above a part of the conveying path atthe location of a downstream end of said supply conveyor, withoutinterfering with the passage of products 10 to be sorted on a sortingunit 2.

With the sorting device 1 a number of discharge conveyors branch off theconveying path for discharging sorted products 11, possibly by way of achute. On the inner side of the conveying path this is the paralleldischarge conveyor 4, whilst on the outer side of the conveying paththere are successively provided three oblique discharge conveyors 5, aparallel discharge conveyor 6 and three perpendicular dischargeconveyors 7, downstream of which only a chute 8 is furthermore provided,without a discharge conveyor connecting thereto. The sorting device 1further comprises a control system (not shown), which is capable ofpushing a product present on the sorting unit 2 off said sorting unit 2,in a manner yet to be described in more detail, at a desired dischargeconveyor 4-7, so that said product is discharged via the dischargeconveyor 4-7 in question.

FIG. 2 is a more detailed view of a part of a sorting unit 2, includingthe part of the sorting device 1 near the sorting unit 2 in question,for the sake of clarity without an associated pusher element yet, whichwill be discussed in more detail yet with reference to FIGS. 4 a and 4b. The sorting unit 2 comprises a carrier plate 21 with a supportingsurface 22 on the upper side thereof. The length of the supportingsurface 22, seen in the conveying direction 3, is about 100 cm. Legs 23are provided at the bottom side of the rectangular carrier plate 21,near the corner points thereof. Casters 24 are mounted to the undersideof the legs 23. The carrier plate 21 is supported on rail sections 29via the legs 23 and the associated casters 24, which rail sections 29extend along the conveying path.

A conveyor chain 31 comprising links 32 extends centrally below thecarrier plate 21. The links 32 are pivotally interconnected aboutvertical pivot axes 37. Provided on the bottom side of each link is aguide wheel 38, which extends between the two upright legs of a U-shapedguide section 39, which extends in an endless path and which defines theconveying path. A driving device 41 is provided for driving the chain31. The driving device 41 comprises friction belts 35 passed overpulleys 34, which engage flat side flanks 33 of the chain 31. To effectan increased contact pressure between the friction belts 35 and the sideflanks 33 of the links 34 of the chain 31, the driving device 41comprises pressure rollers 36, which press the friction belt 35 againstthe side flanks 33 under spring tension. On each of the longitudinalsides of the chain 31, one of the pulleys 34 is driven by a drivingmotor (not shown). Several driving devices 41 may be provided inspaced-apart relationship, depending in part on the length of theconveying path.

At its bottom side the carrier plate 21 is connected to a link 32 of thechain 31 via connecting arms 51 and 52. The connection between theconnecting arms 51 and 52 on the one hand and the carrier plate 21 onthe other hand is such that the carrier plate can pivot about a verticalaxis with respect to the connecting arm 51, 52 in question. It will beunderstood that such pivoting could also be realised via the connectionbetween the respective link 32 and the respective connecting arm 51, 52or in the connecting arm 51 itself.

The connecting arm 52 is made up of two portions 53, 54. The lowerconnecting arm portion 53 is connected to a link 32 and comprises anupright strip 55 in which two horizontal, parallel slotted holes 56 areprovided. The upper connecting arm portion 54 comprises two stripmembers 57 spaced some distance apart. The strip member 55 of the lowerconnecting arm portion 53 extends between the strip members 57 of theupper connecting arm portion 54. The two connecting arm portions 53, 54are connected via two bolt-nut combinations 54, the respective bolts ofwhich extend through the respective slotted holes 56. Thus the upperconnecting arm portion 54 can move reciprocatingly parallel to theconveying direction with respect to the lower connecting arm portion 53,so that passage through bends is possible in spite of the fact that thecarrier 21 is connected to the chain 31 at two successive positions, inwhich bends the connecting arm portions 53, 54 will move relative toeach other, therefore.

The sorting unit 2 further comprises guides 61, 62 at the front side andthe rear side, respectively, of the carrier plate 21, which guidesextend transversely to the conveying direction 3. The guides 61, 62directly connect to the carrier plate 21, which means that no chinks onwhich the products to be sorted might catch are present between theguides 61, 62 on the one hand and the carrier plate 21 on the otherhand.

FIG. 3 shows a sorting unit 102 which is used in a sorting device 101.The sorting device 101 and the sorting units 102 are to a significantextent comparable to the sorting device 1 and the sorting units 2,respectively. In FIG. 3 corresponding elements are therefore indicatedby the same numerals as in FIG. 2, and a more detailed description ofsaid elements need not be given.

The carrier plate 121 is connected to the chain 131 via one extendableconnecting arm 151 instead of by two connecting arms. Guide wheels 125are provided on the outer sides of the legs 123 for guiding the sortingunits 102 in the conveying direction 3. The guide wheels 125 run againsttwo opposite guide strips 126, one of which is shown along a limitedpart of the length of the conveying path in FIG. 4 a, but which mayactually extend the entire length of the conveying path and which helpto ensure that the casters 24 will continue to run on the rail sections29. The links 132 of the chain 131 each consist of two link portions181, 182, which are pivotally interconnected not only about the verticalpivot axis 37 but also about the horizontal pivot axis 183. This enablesthe chain 131 to extend in a three-dimensional path, as a result ofwhich also the conveying path may be three-dimensional. Morespecifically, the chain 131 makes it possible to design the conveyingpath associated with the sorting device 101 to include vertical bends aswell, as is shown on the left-hand side in FIG. 3.

FIG. 4 a shows two successive sorting units 2, including an associatedpusher element 201. The pusher element 201 moves along with itsassociated sorting unit 2 along the entire length of the conveying path.The pusher element 201 comprises a telescopic push arm 202, whichextends just above the carrier plate 21, along the entire lengththereof. The push arm 202 is of the telescopic type and comprises ahollow arm portion 203 at one end and an arm portion 204 inserted intothe hollow arm portion 203 at the other end. Alternatively, twotelescoping sections, for example U-shaped sections, might be used. Atits ends the push arm 202 is pivotally connected to at leastsubstantially horizontal U-shaped guide members 207, 208, respectively,about vertical pivot axes 205, 206. The guide members 207, 208 arearranged for guiding cooperation with guides 61, 62, respectively,associated with the sorting unit 2 in question for guiding therespective guide members 207, 208 in a direction transversely to theconveying direction 3, parallel to the longitudinal direction of theguides 61, 62. The exact manner in which the guide members 207, 208co-operate with the guides 61, 62 is not essential within the frameworkof the present invention. Said guidance might be realised via a slidingcontact, for example, but also by using guide rollers. It is important,however, that the spacing between the guide member 207 and the guidemember 208, seen in the conveying direction 3, remains constant, towhich end a guide groove (not shown) may be provided in the bottom sideof the guides 61, 62, in which guide groove the upright edge 209 presenton the lower horizontal leg of the guide members 207, 208 extends (seeFIG. 4 b). In this way a form-locked guidance is realised.

At the bottom side of each of the guide members 207, 208, a guideelement configured as a mounted axle 210 is pivotally connected to thelower leg of each of the guide members 207, 208 about a vertical pivotaxis. The pivot axes in question coincide with the pivot axes 205, 206.The mounted axle 210 comprises a strip 211 with three guide wheels 212,213, 214 arranged one behind the other mounted thereunder. The guidewheels 212, 213, 214 normally run in one of the two at leastsubstantially U-shaped guide sections 220, 221 disposed on either sideof the conveyor chain 31, which may extend along the entire length ofthe conveying path on either side of the guide section 39. A stationaryguide 222 in the form of a U-shaped section extends below the carrierplate 21 but above the chain 31, at an angle to the conveying direction,at a sorting location, more specifically at the location of a dischargeconveyor 4-7. The stationary guide 222 forms a connection between thetwo guide sections 220, 221. At the location where the stationary guide222 branches off the guide section 221 a switch 231 is provided, whichcan be pivoted forward and backward about the vertical pivot axis 233 inthe directions indicated by the double arrow 234 by suitably energizingthe actuator 232.

In the position of the switch 231 shown in FIG. 4 b, the mounted axle210 will move into the stationary guide 222, causing the guide member208 to move from the guide section 221 towards the guide section 220during movement of the sorting unit 2 in question in the conveyingdirection 3. Since the spacing between the guide members 207 and 208 atleast initially increases in an absolute sense, the length of the pusharm 202 will likewise increase as a result of the arm portion 204telescoping out of the hollow arm portion 203.

In order to enable the connecting arms 51, 52 to pass the stationaryguide 222, said guide is interrupted over a short distance in the centreof its length, at the location indicated at 235. Since the mounted axle210 is provided with three guide wheels 212, 213, 214 arranged onebehind the other, the guiding cooperation between the mounted axle 210and the stationary guide 222 will be maintained also at the location ofthe interruption 235. Since the guide member 208 will move in adirection transversely to the conveying direction 3 from the guidesection 221 to the guide section 220, the push arm 202 will take up anoblique orientation relative to the conveying direction 3. Upon passageof the mounted axle 210 associated with the rear guide member 207, theguide member 207 will also move into the stationary guide 222, with thepush arm 202 extending in the same orientation directly above thestationary guide 222.

After the mounted axle 210 of the rear guide member 207 has passed theswitch 231, energizing the actuator 232 will return the switch 231 tothe position in which the switch 231 extends on the inner side of theguide section 221 and a next mounted axle will pass the switch 231 andcontinue to move in the guide section 221.

Since the stationary guide 222 connects to the guide section 220, themounted axles 210 associated with the respective guide members 208, 207will move into the guide section 220 at a location past the stationaryguides 222, during which passage the arm portion 204 will telescope intothe hollow arm portion 203 and the push arm 202 will assume a shorterlength again.

Alternatively it is also conceivable for the push arm 202 to have afixed length, for example a length equal to the length that the push arm202 has at the front sorting unit 2 in FIG. 4 a, in which the push arm202, besides being pivotally connected to the guide members 207, 208, isalso slidably connected to one of said guide members 207, 208. Thiswould mean, however, that the push arm 202 would extend on the frontside of the guide 62 and/or on the rear side of the guide 61 to alimited extent, which might lead to two successive push arms 202 cominginto contact with each other in inside bends if the push arms arepositioned on that side of the bend. To solve this problem, push arms202 might be configured in such a manner that they can nest together, atleast in an overlap area.

FIG. 5 a shows how products, such as pieces of luggage 224, can besorted out at a sorting location by the push arm 202 pushing the product224 off the supporting surface 22 of the carrier plate.

FIG. 5 b shows an embodiment which has been modified to a limitedextent, in which two parallel stationary guides 251, 252 are used at asorting location instead of one stationary guide 222. Switches areprovided at the location where the stationary guides 251, 252 branch offthe guide section 221, such as the switch 231 that has been explainedabove with reference to FIG. 4 b. By suitably controlling said switchesit is possible to have the mounted axles 210 associated with a sortingunit 2 run into the various stationary guides 251, 252 simultaneously,as a result of which the push arm 202 remains oriented parallel to theconveying direction 3 during lateral movement thereof transversely tothe conveying direction 3, which leads to an advantageous situation inparticular in the case of a perpendicular discharge conveyor 7 or aparallel discharge conveyor 4, 6. The oblique orientation of the pusharm 202 in FIG. 5 a might be suitable in particular for use with theoblique discharge conveyor 5 and is in particular important when piecesof luggage are to be conveyed.

Using the sorting device 1 it is in principle possible to sort outproducts both towards the inner side and towards the outer side of theconveying path, also if products are only supplied from the outer side,for example by means of the supply conveyors 19 in FIG. 1. As the figureshows, the pusher element 201 associated with the sorting unit 2 islocated on the outer side of the conveying path at the location of theend of the front supply conveyor 19, with the end of the supply conveyor19 being positioned directly above the push arm 202, as a result ofwhich loading of the sorting unit 2 in question takes place past theupper side of the push arm 202, thus making it possible to sort outproducts on the inner side, for example at the location of the paralleldischarge conveyor 4.

FIG. 6 shows four successive sorting units 301, which form part of anendless train (not shown) of sorting units 301. For clarity ofillustration the associated pusher elements, which are comparable to thepusher elements 201, are not shown. Each sorting unit 301 comprises acarrier configured as a rectangular carrying blade 302. Each sortingunit 301 is provided both at the front side and at the rear side of thecarrying blade 302 with a closing element configured as a substantiallyD-shaped (whether or not in mirror image), seen in top plan view,closing blade 303, 304 having convex outer edges 305, 306. The outeredges 305 have an angular shape with straight parts, whilst the outeredges 306 are curved. The convex shape of the outer edges 305 and 306enables the sorting units to pass through bends without the associatedclosing blades 303 and 304 colliding with an adjacent sorting unit, asis clearly shown in FIG. 6.

The closing blades 303, 304 overlap, with the closing blade 303extending above the associated closing blade 304 at least in theoverlapping area. It is conceivable in that regard that each closingblade 304 is supported on a link of an drive chain extending therebelowvia a connecting arm comparable to the connecting arm 51, 52 or 151. Theclosing blades 304 are made up of a strip-shaped part 307 and a slightlylower part 308 provided with the curved edge 306. The strip-shaped part307 and the lower part 308 are connected to each other via a verticalstrip member 309. Guide slots 314, 315 are provided between the carryingblades 302 and the closing blades 303, 304 for guiding guide members,such as the guide members 207, 208.

Segmental further closing elements 311 are provided between theoverlapping closing blades 303, 304, more specifically between theclosing blade 303 and the lower part 308 of the closing blade 304, nearthe longitudinal edges, at the location where, in a rectilinear part ofa conveying path, the convex edges 305, 306 of the closing blades 303,304 define at least substantially triangular surfaces 310 within thewidth of the sorting units 301, on the longitudinal sides of saidsorting units 301. Said further closing elements 311 are pivotallyconnected to the closing blade 303 about vertical pivot axes 312 locatednear the point of the segmental shape of said further closing elements.Said further closing elements 311 tend to pivot in the directionindicated by the arrow 313 under the influence of a torsion spring (notshown), causing said further closing elements 311 to abut against anassociated vertical strip member 309 with a point thereof.

The abutment of the closing element 311 against the vertical stripmember 309 will cause further closing elements 311 located on the sideof an inside bend to pivot inwardly against the action of the torsionspring and move below the associated closing blade 303 in theirentirety. A triangular free area as described above is altogether absentin the inside bend.

In the outside bend, on the other hand, the triangular free area becomeslarger. In order to be able to follow this shape, as it were, as itbecomes larger and to continue to cover said area as well as possible,the closing elements 311 located on the side of an outside bend arecarried along by the closing blade 303. The closing blade 303 is to thatend provided with a downwardly extending projection at the locationindicated by reference numeral 313, whilst the further closing element311 is provided with an upwardly extending projection, which is engagedby said downwardly extending projection to move along therewith.

As a result of the use of the closing blades 303 and 304, the areabetween the carrying blades 302 of successive sorting units 301 isscreened. This effect is further enhanced by the action of the furtherclosing elements 311.

Incidentally, it is noted that if the conveying path would only comprisebends having the same orientation, the closing blades 303, 304 wouldonly need to be bevelled/rounded on one side, viz. on the side of theinside bend(s), in which case the closing blades 303, 304 would berectangular in shape on the side of the outside bend(s) and no furtherclosing elements 311 would be needed there. In that connection it isalso possible, for example, for the closing elements, which are onlyused on one longitudinal side, therefore, to have a vertical pivot axisextending through an associated closing blade on the outer side of thesorting unit.

1. A sorting device for sorting products, comprising: a plurality ofsorting units; conveying means for moving the sorting units in aconveying direction along a conveying path, said sorting units eachcomprising a carrier including a supporting surface for supporting aproduct to be sorted; removing means for moving the product to be sortedoff the supporting surface at a desired sorting location, wherein theremoving means comprises for each sorting unit a pusher element disposedabove the supporting surface of the respective sorting unit, as well asmoving means for moving the pusher element laterally at a sortinglocation so as to have the pusher element push the product to be sortedoff the supporting surface, wherein the removing means comprises twoguides for each sorting unit for guiding two respective guide members ofthe pusher element during said lateral movement of the pusher element;wherein the moving means comprises at least one stationary guidedisposed under the supporting surface at a sorting location, which guideextends at an angle to the conveying direction, as well as at least oneguide element connected to a pusher element for each sorting unit forguiding cooperation of said at least one guide element with said atleast one stationary guide during transport of the sorting unit; whereinthe moving means comprises two guide elements for each sorting unit,which two guide elements are connected to the respective two guidemembers of the pusher element and which are each arranged for guidingcooperation with said at least one stationary guide.
 2. A deviceaccording to claim 1, wherein the two guide elements are pivotallyconnected to the respective two guide members about respective verticalpivot axes.
 3. A device according to claim 1, wherein the two guidemembers are provided on two opposite ends of the pusher element.
 4. Adevice according to claim 1, wherein the two guide elements are provideddirectly below the respective two guide members.
 5. A device accordingto claim 1, wherein at least one guide member is pivotally connected toanother part of the pusher element about a further pivot axis extendingperpendicularly to the supporting surface of the sorting unit.
 6. Adevice according to claim 1, wherein the two guide members are pivotallyconnected to another part of the pusher element about two respectivefurther pivot axes extending perpendicularly to the supporting surfaceof the sorting unit.
 7. A device according to claim 1, wherein at leastone guide member is slidably connected, in a direction parallel to thesupporting surface, to another part of the pusher element.
 8. A deviceaccording to claim 1, wherein the length of the pusher element isvariable.
 9. A device according to claim 8, wherein the pusher elementis of telescopic type.
 10. A device according to claim 1, wherein themoving means comprises two successive stationary guides disposed underthe supporting surface at a sorting location, which guides extend at anangle to the conveying direction, with which two guides the tworespective guide elements can cooperate simultaneously during transportof the sorting unit.
 11. A device according to claim 10, wherein the twostationary guides extend parallel to each other.
 12. A device accordingto claim 1, wherein the two guides are provided on two opposite sides,seen in the conveying direction, of the supporting surface of thesorting unit.
 13. A device according to claim 1, wherein the two guideelements are directly connected to the two respective guide members. 14.A device according to claim 1, wherein the conveying means comprises adriven chain, to which each of the sorting units is connected.
 15. Adevice according to claim 14, wherein the conveying means comprisesfriction-type drive means, which frictionally engage flanks of the chainfor driving the chain.
 16. A device according to claim 14, wherein thesorting units are pivotally connected to the chain about two stillfurther pivot axes extending perpendicularly to the supporting surfaceat two connecting positions located one behind the other, seen in theconveying direction, whilst the sorting units are slidably connected tothe chain at the location of at least one of the two connectingpositions.
 17. A device according to claim 14, wherein the chain extendscentrally below the sorting units, seen in a direction transversely tothe conveying direction.
 18. A device according to claim 1, wherein saidsupporting surface is a closed surface.
 19. A device according to claim1, wherein a supply conveyor is provided for supplying products to besorted to a sorting unit, with a downstream end of said supply conveyorterminating at a higher level than the upper side of pusher elementspassing the downstream end of the supply conveyor.
 20. A deviceaccording to claim 19, wherein the downstream end of the supply conveyorat least partially extends directly above a part of the passing pusherelements.
 21. A device according to claim 1, wherein the sorting unitseach include a closing element both at a front end and at a rear end ofthe carrier for closing a gap between the carrier and an adjacentcarrier, wherein closing elements of successive sorting units partiallyoverlap and have an at least substantially convex edge at their facingsides, at least on one longitudinal side of the sorting units.
 22. Adevice according to claim 21, wherein convex edges of closing elementsof successive sorting units define at least substantially triangularareas within the width of the sorting units in a rectilinear part of theconveying path on at least one of longitudinal sides of the sortingunits, which areas are at least partially closed by a further closingelement, which is movably connected to one of said closing elements. 23.A device according to claim 22, wherein said further closing element ispivotally connected to one of the closing elements about a verticalclosing pivot axis.
 24. A device according to claim 23, wherein saidfurther closing element is segmental in shape, with said verticalclosing pivot axis extending near a point of the segmental shape.
 25. Adevice according to claim 22, wherein said further closing element abutsagainst a stop member under spring pressure.
 26. A device according toclaim 1, wherein the sorting units are pivotally interconnected about avertical pivot axis.